So...it's been a few days working on tongue and groove for my gypsy caravan. I had 1.5mm bass wood which I used for the sides and it worked beautifully. However I then ran out of that! Unfortunately here in NZ there aren't many craft shops around that stock that type of thing. I drove 45mins to get to a hobby shop that does stock bass wood, but they only had 1mm or 3mm +. So I decided to get the 1mm - easier to work with than the 2mm I had at home. They also had .5mm mahogany strips which I bought a few of - thinking it could be trim or similar as the furniture for the inside is all mahogany. So, came home and spent a whole afternoon making up patterns for the two ends, cutting the wood to shape, measuring the lines and grooving them as I had done with the others, using an embossing tool. I primed the first small pieces which were the bottom side strips. Then found when I came to sand them that the grooves had completely disappeared. So the 1mm tongue and groove was useless and went into the rubbish. I had to start again with 2mm. The T&G was so much better in the 2mm, but the cutting was doubly hard as the 1.5mm! Talk about a sore hand, wrist, fingers, arms - blisters! Still....the end is worth it! it's all glued on now and I just need to tidy up the raw edges.